A disposable plastic container and tubing set is typically used for collecting blood or blood components from a donor. For many years such containers have incorporated labels containing bar codes that include a description of the container type and the product code information assigned by the U.S. Food and Drug Administration for the intended contents of the container, for example whole blood, red blood cells or platelets or other components. There are significant limitations to bar code labels. Among these is the requirement that a bar code be in the line of sight of a scanner. Not only does this mean that each individual bar code must be made accessible to the scanner, but also the bar code itself cannot be degraded or obscured in any way. Since the bar codes are susceptible to being folded or crumpled, a technician is often required to manually straighten or smooth them out to make them readable. Also, the labels on frozen blood containers can become encrusted with ice, which can make the bar code unreadable.
It has been previously generally proposed to use radio frequency identification (“RFID”) tags with blood bags for tracking purposes and to avoid some of the drawbacks associated with barcode labels. For purposes of this description, RFID “tag” is used in accordance with its well-known and ordinary meaning, in which it includes a microcircuit or microchip combined with an antenna, allowing it and the object to which it is attached to be tracked via wireless communication. RFID “data source” may be used interchangeably with RFID “tag” herein, and no distinction is intended.
Turning back to the discussion, there have been issues with the use of RFID tags in connection with blood containers. First, the tag must adhere to the international ISBT128 data integrity standard governing blood bag labeling. Second, the tag cannot create a risk of contaminants leaching into the blood. Third, the tag must survive for long durations at a wide temperature range, including steam sterilization, pasteurization and/or long periods at sub-freezing temperatures. These requirements make the incorporation of an RFID tag in a blood container a non-trivial matter.
It has been suggested that if an RFID tag is simply adhered in a flat planar configuration on the blood container, the fluid in the container will absorb the electromagnetic waves, rendering communication between the RFID tag and the reader/writer unreliable or impossible. See U.S. Pat. No. 7,703,687, which is incorporated by reference herein. Furthermore, since the blood container is typically soft and pliable, if the RFID tag is simply adhered on the blood container, ordinary handling of the blood container has a tendency to flex the RFID tag and may cause separation of the tag's antenna from the rest of the tag's circuit. The U.S. Pat. No. 7,703,687 addresses these issues by using a stand-off mounting label that has a mounting part for adhering to the container and a holding part foldably connected to the mounting part. The holding part mounts the RFID tag and can be flexed to dispose the tag in a plane separate from that of the mounting part.
Other arrangements for securing an RFID tag to a blood container are shown in U.S. Pat. No. 6,285,285, also hereby incorporated by reference. Several of these entail placing the RFID tag directly on the body of the container, with the tag either held in its own bag or retained by film layers attached to the container walls. The U.S. Pat. No. 6,285,285 also shows extensions of the container walls forming a compartment for receiving the tag.